Answer:
D. About 800 years
Step-by-step explanation:
Use the half-life equation:
A = A₀ (½)ⁿ
where A is the final amount,
A₀ is the initial amount,
and n is the number of half-lives.
0.90A₀ = A₀ (½)ⁿ
0.90 = (½)ⁿ
To solve for n, take log of both sides:
log 0.9 = n log 0.5
n = (log 0.9) / (log 0.5)
n = 0.152
It takes 0.152 half-lives. The half-life of carbon-14 is 5730 years.
0.152 × 5730 years = 871 years
The closest answer is D.
Tom is correct, and Dan is wrong. A quadrilateral is a closed figure with four sides, for example, like a kite. A parallelogram is a four sided rectangular figure with opposite sides that are parallel.
Answer:
y = 
x + 7
Step-by-step explanation:
the equation of a line in point- slope form is
y - b = m(x - a)
where m is the slope and (a, b ) a point on the line
y - 8 = - 
(x + 5) ← is in point- slope form
with m = -
given a line with slope m then the slope of a line perpendicular to it is
= - 
= - 
=
the equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept ) , then
y = x + c ← is the partial equation
to find c substitute (- 6, - 2 ) into the partial equation
- 2 = - 9 + c ⇒ c = - 2 + 9 = 7
y = x + 7 ← equation of line K
For this case we have the following variables:
x = the number of drill-based workouts
y = the number of conditioning workouts
The system of equations that adapts to the situation is:
"According to her schedule, she can complete at most 10 workouts this week":
x + y <= 10
"It takes Gianna 45 minutes to complete her drill-based workouts and 30 minutes to complete her conditioning workouts. She is required to spend more than 450 minutes on workouts every week"
45x + 30y> 450
Answer:
A system of inequalities can that be used is:
x + y <= 10
45x + 30y> 450
